APPLETON, Wis. — Offering big rewards for leads in cold cases doesn't tend to be any more effective than offering more modest amounts, experts in Wisconsin say.

Rewards of $10,000 or more can create false leads without increasing the chances of solving the case, the Post-Crescent Media reported (http://gbpg.net/156Sgky ). But that doesn't stop some families from offering big money, saying they do it because they hope every effort helps.

David Byrnes, the treasurer of Green Bay Area Crime Stoppers, said his group caps rewards at $1,000 because larger rewards can be less effective.

"Beyond $1,000 you really run into problems with multiple people saying they have information, just to get the reward," Byrnes said.

Small to moderate amounts seem to be just as effective as larger amounts, said Mike Scott, clinical professor of law at the University of Wisconsin.

Dawn Gunderson knew the statistics when she and her family offered a reward for information in her mother's 2006 homicide. Connie Boelter had been slain in her Appleton home, and no arrest had been made for months, so Gunderson and two siblings offered a $10,000 reward.

Gunderson said she was told that larger rewards like hers don't increase the chances of solving a crime. But she said she and her siblings did it because they hoped it would draw attention to the case.

"The detectives are pretty adamant — and we agree with them — that somebody out there knows something," Gunderson said. "It's not in the news all the time. It's not being talked about all the time."

Even when a large reward does lead to an arrest, there still could be problems, Byrnes said. Sometimes the people who offered the money decline to pay. In other cases the money might be gone if it takes several years for a key lead to trickle in. There also could be disputes over the degree to which a specific tip leads to an arrest, prompting arguments over whether the tipster has earned the reward.

In Racine County the average amount paid for a valuable tip is about $122, said K. Scott Abrams, president of the state's Crime Stoppers organization.

"It's not the amount of money out there that encourages someone to make tip. It's the ability to leave (an) anonymous tip, and not have a squad (car) in front of their house," Abrams said.